It’s common for cars to already have very light window tint coming out of the factory. The windows may look clear, but they usually don’t let all of the light through. Anyway, you can easily get window tint installed by consulting any window tinting professional. If you’d like to tint your windows yourself, DIY window tinting kits are also available. Either way, you’ll need to understand how window tint percentages work to make sure you keep your car’s window tint within legal limits, according to your state’s regulations.

Window tint is regulated by law for various road safety reasons.

How Does Tint Percentage Work?

Your window tint is measured by the percentage of light that can pass through it, which is called visible light transmission (VLT). If the percentage is higher, it means more light is visible through the tint, which appears lighter. Lower VLT percentages appear darker because less light is able to pass through the tint.

It’s possible to tint your windows from 5% to 90%. However, window tint is regulated by law for various road safety reasons. You can get pulled over and fined if your window tint doesn’t comply with state regulations.

How to Calculate Window Tint Percentage

Whether you plan on getting your car professionally tinted or doing it yourself, you’ll need to understand how window tint percentage is calculated to make sure you don’t go beyond your state’s window tint limits. If your car’s windows are clear, it’s easy to determine. However, your vehicle may already have an existing window tint. If so, you’ll need to calculate the output VLT percentage by multiplying the percentages of both existing tint and the additional tint you’ll be installing.

For example, your window has an existing VLT of 80% and you’d like to make it darker by installing a window tint film with 50% VLT. To get the combined VLT percentage, you need to multiply the VLT of the glass with the VLT of the film. In this case, that would be (0.50 x 0.80) x 100 =40% VLT. This means you’ll end up with a 40% VLT tint after installing your film. It’s best you calculate accordingly even before purchasing window tint film to make sure you stay within state legal window tint levels.

How Dark Should You Tint Your Car Windows?

Legal window tint percentages may vary depending on the state you live in. Some states allow a wide range in terms of how dark your window tint can be, but it’s best to not push it too far and keep it within your comfort level. Dark window tint can compromise your vision in low-light conditions, so you shouldn’t make your tint too dark so that you can avoid accidents.

What Is The Darkest Window Tint That’s Legal?

Most states allow up to 50% VLT for the driver’s and passenger’s front windows.

Most states allow up to 50% VLT for the driver’s and passenger’s front windows. For the rear passenger and side windows as well as the back window, the most common limit is 35% VLT. You can go darker depending on the indicated window tint limits of the state where you live.

Legal Window Tint Levels According to State

Window Tint Terms and Definitions

Tint darkness is presented by visible light transmission (VLT) percentage.
Front side windows are the driver’s and passenger’s adjustable windows at the front.
Rear side windows are the rest of the side windows, including the rear-seat passenger windows.
A shade band is a rectangular band of window tint film located at the top of the windshield which extends downwards.
The AS1 line is a marking around the upper corner sides of the windshield left by its glass manufacturer.
Tint reflection refers to the window tint’s reflective or metallic feature.
VLT percentages parted by a slash (/) means that the first value is for cars and the next number is for SUVs or vans.

State	Front Side Windows	Rear Side Windows	Back Window	Windshield Shade Band Height	Reflectivity
Alabama	32%	32% / No limit	32% / No limit	6 in.	Up to 20% reflective
Alaska	70% / No limit	40% / No limit	40% / No limit	5 in.	Non-reflective
Arizona	33%	No limit	No limit	Until AS1 line	Up to 35% reflective
Arkansas	25%	25% / 10%	10%	5 in.	Non-reflective
California	70%	No limit	No limit	4 in.	Non-reflective
Colorado	27%	27%	27%	4 in.	Non-reflective
Connecticut	35%	35% / No limit	No limit	Non-reflective tint above the AS1 line	Front windows up to 21% reflective / Rear windows up to 27% reflective
Delaware	70%	No limit	No limit	Until AS1 line	Non-reflective
Florida	28%	15%	15%	Non-reflective tint until AS1 line	Up to 25% reflective
Georgia	32%	32% / No limit	32% / No limit	6 in.	Up to 20% reflective
Hawaii	35%	35% / No limit	35% / No limit	no inch limit, tint must be 70%	Non-reflective
Idaho	35%	20% / No limit	35% / No limit	Until AS1 line	Up to 35% reflective
Illinois	35%	35% / No limit	35% / No limit	6 in.	Non-reflective
Indiana	30%	30% / No limit	30% / No limit	Until AS1 line	Up to 25% reflective
Iowa	70%	No limit	No limit	Until AS1 line	Non-reflective
Kansas	35%	35%	35%	Until AS1 line	Non-reflective
Kentucky	35%	18% / No limit, 8 in. from top	18% / No limit, 8 in. from top	Until AS1 line	Up to 25% reflective
Louisiana	40%	25% / No limit	12% / No limit	Until AS1 line	Up to 20% reflective
Maine	35%	35% / No limit	35% / No limit	4 in.	Must be Non-reflective
Maryland	35%	35% / No limit	35% / No limit	5 in.	No limit
Massachusetts	35%	35%	35%	6 in. or until AS1 line	Up to 35% reflective
Michigan	4 in. from top only, No limit	No limit	No limit	4 in.	Up to 35% reflective
Minnesota	50%	50% / No limit	50% / No limit	No shade band	Up to 20% reflective
Mississippi	28%	28% / No limit	28% / No limit	Until AS1 line	Up to 20% reflective
Missouri	35%	No limit	No limit	Until AS1 line	Up to 35% reflective
Montana	24%	14% / No limit	14% / No limit	Until AS1 line	Up to 35% reflective
Nebraska	35%	20% / 35%	20% / 35%	5 in. or until AS1 line, whichever comes first	Up to 35% reflective
Nevada	35%	No limit	No limit	Until AS1 line	No limit
New Hampshire	no tint	35% / No limit	35% / No limit	6 in.	Non-reflective
New Jersey	no tint	No limit	No limit	no tint	Non-reflective
New Mexico	20%	20% / No limit	20% / No limit	5 in. or AS1 line, whichever comes first	No limit
New York	70%	70% / No limit	No limit	6 in.	Non-reflective
North Carolina	35%	35% / No limit	35% / No limit	Until AS1 line	Up to 20% reflective
North Dakota	50%	No limit	No limit	Up to 70% to whole windshield	Non-reflective
Ohio	50%	No limit	No limit	Up to 70% to whole windshield	No more reflective than a standard window
Oklahoma	25%	25% / No limit	25% / No limit	5 in. or until AS1 line, whichever comes first	Up to 20% reflective
Oregon	35%	35% / No limit	35% / No limit	6 in.	Up to 13% reflective
Pennsylvania	70%	70% / No limit	70% / No limit	No tint	Non-reflective
Rhode Island	70%	70% / No limit	70% / No limit	Until AS1 line	No limit
South Carolina	27%	27% / No limit	27% / No limit	Until AS1 line	Must be Non-reflective
South Dakota	35%	20% / No limit	20% / No limit	Until AS1 line	Non-reflective
Tennessee	35%	35%	35%	Until AS1 line	Non-reflective
Texas	25%	No limit	No limit	5 in. or until AS1 line, whichever comes first	Up to 25% reflective
Utah	43%	No limit	No limit	Until AS1 line	Non-reflective
Vermont	no tint	No limit	No limit	Until AS1 line	Non-reflective
Virginia	50%	35% / No limit	35% / No limit	Until AS1 line	Up to 20% reflective
Washington	24%	24% / No limit	24% / No limit	6 in.	Up to 35% reflective
Washington, D.C.	70%	50% / 35%	50% / 35%	5 in. or Until AS1 line	No limit
West Virginia	35%	35% / No limit	35% / No limit	5 in.	20% reflective
Wisconsin	50%	35%	35%	Until AS1 line	No limit
Wyoming	28%	28% / No limit	28% / No limit	5 in. or Until AS1 line	Up to 20% reflective

Car Window Tinting Advice Based on Window Tint Legal Limits

Check your local window tinting laws before adding tint to your windows. When in doubt, you can simply let professionals handle calculations and installation. They have experience dealing with legal window tint levels, which gives you the reassurance that your car upgrade isn’t breaking any state laws and regulations.

Looking Ahead: The Future of Window Tint

The automotive industry has gone to great lengths to make driving less of a chore and more of a fun activity.

Aside from performance upgrades, several manufacturers have also looked into improving other components that can take ride comfort to the next level一including window tints.

For example, in 2019, Electronic paper manufacturer E Ink has begun developing JustTint, a variable tint film that can digitally change its opacity.

The film has yet to be used for automotive applications. However, BMW took the same vision and brought it closer to the automobile industry when it introduced the iX Flow concept.

BMW introduced an electric SUV concept wrapped in digital tint film that changes hues using laser-cutting film strips.

Adopting this concept could mean that drivers will have the luxury of having different percentages of tint without tearing it from their windows.

They can also adjust the window tint percentage, depending on the temperature and state regulations with a simple push of a button.

Wrapping Up

States have different illegal tint percentages, which is why you must gather all the necessary information before blurting out a random VLT number.

Also, keep in mind that the tint also plays a part in your visibility when driving. Remember that installing a dark tint can compromise your safety, especially when driving in low-light conditions.

About The Authors

Reviewed By Lisa Conant

Automotive Features Reviewer at CarParts.com

Lisa Conant grew up in Canada around a solid contingency of gear heads and DIY motor enthusiasts. She is an eclectic writer with a varied repertoire in the automotive industry, including research pieces with a focus on daily drivers and recreational vehicles. Lisa has written for Car Bibles and The Drive.

Written By CarParts.com Research Team

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